Practice Quiz #1 | Coursera

If for given point directional derivatives coincide for all directions, than the function is differentiable

If partial derivatives exist and there is no directional derivative for some direction than the function is not differentiable

Correct

Correct!

If for given point directional derivatives exist for all directions, then the function is differentiable

Partial derivatives are special case for directional derivatives

Correct

Correct!

- \sqrt{3} + 2

2-sqrt(3)

Correct

This function is differentiable, thus one could use the formula with scalar product and gradient

3

3

Correct

Correct!

e \sqrt{a^{2} + b^{2}}

E*sqrt(a^2+b^2)

Correct

Correct! Simple looking, write?